Fix #890 - Move PubSub usage doc under the right heading.

jgeewax · jgeewax · commit eba50c708a7c · 2015-05-24T10:47:21.000-04:00
diff --git a/docs/index.rst b/docs/index.rst
@@ -14,8 +14,8 @@
   storage-blobs
   storage-buckets
   storage-acl
-  pubsub-usage
   pubsub-api
+  pubsub-usage
   pubsub-subscription
   pubsub-topic
 
